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Book            \cite{press001} \par
Book            \cite{agrawal001}\par
Article         \cite{xuemingliu001}\par
Inproceedings   \cite{woodbury001}\par
Incollection    \cite{agrawal004}\par
Inbook          \cite{mollenauer001}\par
Techreport      \cite{itu.g694.2}\par
Article         \cite{smekal001}\par
Article         \cite{dipascuale001}\par
    \bibliographystyle{plain}
    \bibliography{referencias}
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